In recent years, a superlattice memory in which a layered crystal (GeTe/Sb2Te3) formed by alternately stacking GeTe layers and Sb2Te3 layers between two electrodes is provided receives attention. In this superlattice memory, the resistance value thereof can be changed by the movement of Ge atoms in the layered crystal. For this reason, switching of a current lower than the case of the phase-change memory is enabled, and reduction in power consumption can be achieved.
However, in a cross-point type memory device using the superlattice memory, the limitation on the number of times of rewriting, i.e., setting (writing)/resetting (erasing) of data at each memory cell becomes a problem.